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A180746
Partial sums of A004144.
0
1, 3, 6, 10, 16, 23, 31, 40, 51, 63, 77, 93, 111, 130, 151, 173, 196, 220, 247, 275, 306, 338, 371, 407, 445, 487, 530, 574, 620, 667, 715, 764, 818, 874, 931, 990, 1052, 1115, 1179, 1245, 1312, 1381, 1452, 1524, 1600, 1677, 1756, 1837, 1920, 2004, 2090, 2178
OFFSET
1,2
FORMULA
a(n) = Sum_{i=1..n} A004144(i).
MATHEMATICA
fQ[n_] := If[n > 1, First@ Union@ Mod[ First@# & /@ FactorInteger@ n, 4] != 1, True]; Accumulate@ Select[ Range@ 90, fQ]
CROSSREFS
Cf. A004144.
Sequence in context: A330133 A025701 A025744 * A025714 A025729 A011913
KEYWORD
nonn
AUTHOR
Jonathan Vos Post, Sep 19 2010
EXTENSIONS
a(21) and a(50) corrected by Georg Fischer, Aug 29 2020
STATUS
approved